Does a 7970 support TWO 2650x1440 monitors out of the box?

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RussianSensation

Elite Member
Sep 5, 2003
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If the 2 Korean Monitors only have DVI inputs, what is the minimum graphics card that will run both? eg. for a computer mainly used for office work, not gaming, so a powerful 3D card is not required. Just excellent 2D image quality/clarity wanted.

Thanks

ZOTAC Synergy ZT-40611-10L GeForce GT 430 (Fermi) 1GB 64-bit DDR3 PCI Express 2.0 x16 HDCP Ready Video = $50

Specifications list:

Dual Dual-link DVI (up to 2560x1600 from each DVI port).
PDF: http://www.zotacusa.com/specsheet/ZT-40611-10L.pdf

As far as I am aware, no GTX600 card under GTX660Ti has Dual Dual Link DVI support; so GTX650Ti won't work for 2x 2560x1440 DVI (iirc).

You are welcome!
 
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MavAnan

Junior Member
Jul 7, 2003
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Thanks for that. So do you think the warnings the Korean sellers put on their listings, eg. "Please use DVI-D port only. Cannot be used with DVI-I or DVI-S" are just overkill?
 

mrpiggy

Member
Apr 19, 2012
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This is incorrect. Both DVI-D and DVI-I exist in both single link and dual link form. The graphics card's dual link DVI output can be either DVI-D or DVI-I, so long as it is dual link. However, the input on the monitor is DVI-D, so you need a (again, dual link) DVI-D cable. DVI-I won't fit because it has extra pins


Yeah, he's right. I get them mixed up dual link d vs i..
 

joe_H

Member
May 27, 2010
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I ran two Shimians off my 7950 (had to buy an active DP converter to run the second). However, my 7950 idled around 54C which I thought was too hot. Wound up buying a cheap secondary video card to power the second display. 7950 now idles in the low 30's.
 

mrpiggy

Member
Apr 19, 2012
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I'm not sure I follow. Doesn't this GTX650Ti have dual-link DVI-D and do 2 x 2560x1440?


According to Gigabyte's website, both this one and the cheaper GT640 I linked earlier have 2 x Dual-link DVI-D output so they should support the resolutions on having the two monitors.
 
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MavAnan

Junior Member
Jul 7, 2003
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According to Gigabyte's website, both this one and the cheaper GT640 I linked earlier have 2 x Dual-link DVI output.
Yes I know (as well as all of Gigabytes 650's), that's why I said I'm not sure I follow his statement. ie. "that no GTX600 card under GTX660Ti has Dual Dual Link DVI support".
 

RussianSensation

Elite Member
Sep 5, 2003
19,458
765
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I'm not sure I follow. Doesn't this GTX650Ti have dual-link DVI-D and do 2 x 2560x1440?

You are right, that card supports it.
"Features Dual-link DVI-D*2"

6820_m.jpg


original


According to Gigabyte's website, both this one and the cheaper GT640 I linked earlier have 2 x Dual-link DVI-D output so they should support the resolutions on having the two monitors.

You are right, that one does too.
"Features Dual link Dual Link DVI-D*2"

Last time I checked GTX600 series cards, I didn't see these models for sale yet. That's why I said iirc. My mistake. Looks like some lower end GTX600 cards support dual-link dual DVI-D. Looks like you have at least 2 options from Gigabyte. :thumbsup:
 
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MavAnan

Junior Member
Jul 7, 2003
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ok, but do you think the warnings the Korean sellers put on their listings, eg. "Please use DVI-D port only. Cannot be used with DVI-I or DVI-S" are just overkill? (ie. given that the Zotac card you mentioned above has 2 DVI-I connectors)
 

Black Octagon

Golden Member
Dec 10, 2012
1,410
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ok, but do you think the warnings the Korean sellers put on their listings, eg. "Please use DVI-D port only. Cannot be used with DVI-I or DVI-S" are just overkill? (ie. given that the Zotac card you mentioned above has 2 DVI-I connectors)

It's not overkill. The monitors are supplied with a dual link DVI-D cable to match the dual link DVI-D input port. However, it really doesn't matter whether the dual link DVI port on your graphics card is -D or -I

DVI-D - digital
DVI-I - capable of both digital AND analogue (so it has more pins)

Edit: in other words they say port when they should say cable.
 

MavAnan

Junior Member
Jul 7, 2003
24
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It's not overkill. The monitors are supplied with a dual link DVI-D cable to match the dual link DVI-D input port. However, it really doesn't matter whether the dual link DVI port on your graphics card is -D or -I

DVI-D - digital
DVI-I - capable of both digital AND analogue (so it has more pins)

Edit: in other words they say port when they should say cable.
Ok, that's an interesting interpretation, ie. that that particular Seller mistakenly used the word port when meaning to say cable ... as opposed to the overkill explanation (and especially since they supply the cable anyway).

Given that a number of Sellers give warnings to the same effect as the one above, eg.:

"Your video card must have 2pcs x DVI-D Dual output."

"If you want to make dual monitor by 2pc x this Monitor, video card must have 2pcs x DVI-D dual output."

... it seems more likely they're just being overly cautious. I'm not saying they're right but it looks more like overkill than a typo.
 

Black Octagon

Golden Member
Dec 10, 2012
1,410
2
81
Ok, that's an interesting interpretation, ie. that that particular Seller mistakenly used the word port when meaning to say cable ... as opposed to the overkill explanation (and especially since they supply the cable anyway).

Given that a number of Sellers give warnings to the same effect as the one above, eg.:

"Your video card must have 2pcs x DVI-D Dual output."

"If you want to make dual monitor by 2pc x this Monitor, video card must have 2pcs x DVI-D dual output."

... it seems more likely they're just being overly cautious. I'm not saying they're right but it looks more like overkill than a typo.

Mate, I fully understand your concern, really I do. My interpretation is based on having read countless forum threads about these Korean eBay IPS screens for the better half of the past 12 months. This question has come up many, many times by people (like yourself) who are legitimately confused by what these Korean sellers state in their Item Descriptions (there are other problematic things like stating that only cards up to the HD6XXX and GTX5XX generations are supported, for example).

I have this card: http://www.tigerdirect.com/applicati...?EdpNo=1777551

See how its DL-DVI port is DVI-I? Well I have it connected to one of these so-called DVI-D only monitors, and it works, trust me :)

Also, have a read of this:
1) http://answers.yahoo.com/question/index?qid=20080723110016AAiqzDG
2) http://hardforum.com/showpost.php?p=1038896395&postcount=21
3) http://forums.overclockers.co.uk/showpost.php?p=22111864&postcount=1783
4) http://forums.overclockers.co.uk/showpost.php?p=22112045&postcount=1786
5) http://www.tomshardware.co.uk/forum/372435-15-getting-dual-crossover-monitors-work-evga
 

MavAnan

Junior Member
Jul 7, 2003
24
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Mate, I fully understand your concern, really I do. My interpretation is based on having read countless forum threads about these Korean eBay IPS screens for the better half of the past 12 months. This question has come up many, many times by people (like yourself) who are legitimately confused by what these Korean sellers state in their Item Descriptions (there are other problematic things like stating that only cards up to the HD6XXX and GTX5XX generations are supported, for example).

I have this card: http://www.tigerdirect.com/applicati...?EdpNo=1777551

See how its DL-DVI port is DVI-I? Well I have it connected to one of these so-called DVI-D only monitors, and it works, trust me :)

Also, have a read of this:
1) http://answers.yahoo.com/question/index?qid=20080723110016AAiqzDG
2) http://hardforum.com/showpost.php?p=1038896395&postcount=21
3) http://forums.overclockers.co.uk/showpost.php?p=22111864&postcount=1783
4) http://forums.overclockers.co.uk/showpost.php?p=22112045&postcount=1786
5) http://www.tomshardware.co.uk/forum/372435-15-getting-dual-crossover-monitors-work-evga

Mate, I appreciate your concern but I think it's misplaced. With all due respect, I think there's a little confusion about the meaning of the above few posts. I'm not "concerned" by what Korean Sellers have written in their ebay descriptions, I was simply offering an explanation for the statements, ie. overkill - they're being overly cautious. And I have no idea why you flat out said "It's not overkill" but rather consistent typos when overkill appears to be the more likely explanation (unless there is some truth to the Seller's statements in certain dual monitor situations).

There has never been any doubt that a card with a dual-link DVI-I port will work to drive a single Korean Monitor.

The only question was re two Monitors, ie. whether cards with a DVI-I x 2 or DVI-I plus DVI-D configuration would have any problem driving two of these monitors, and if they do whether there's any difference.

From some posts it seems that such cards probably can. But that was the salient question - as well as:- If running 2 Korean Monitors, will a card with DVI-D x 2 have any advantage over DVI-I x 2 or DVD-I plus DVI-D?
 

Black Octagon

Golden Member
Dec 10, 2012
1,410
2
81
There has never been any doubt that a card with a dual-link DVI-I port will work to drive a single Korean Monitor.

Fair play, TBH I was mixing up (in my mind) my response to you with my earlier response to mrpiggy, who was under the impression that DVI-I wouldn't work: http://forums.anandtech.com/showpost.php?p=34528202&postcount=22

I'm not "concerned" by what Korean Sellers have written in their ebay descriptions, I was simply offering an explanation for the statements, ie. overkill - they're being overly cautious. And I have no idea why you flat out said "It's not overkill" but rather consistent typos when overkill appears to be the more likely explanation (unless there is some truth to the Seller's statements in certain dual monitor situations).

Ok I see what you mean. Indeed it could be overkill I suppose, especially if that's what the manufacturer has told them. It could be one reason why they make strange declarations like saying that the HD5850 is incompatible even though its DVI port is Dual Link (AFAIK all DVI ports on 5850s are DVI-I and not DVI-D).

While it could be them being overly cautious because of what the manufacturer tells them, I also think it's possible that they're confusing Dual Link DVI and DVI-D, as happens very often. They could also have noticed that a DVI-I cable has too many pins to fit into the monitors' input. So when I said "in other words they say port when they should say cable," I didn't mean that it was a typo, but rather that they are posting incorrect information because they hold a commonly-held misunderstanding about DVI.

Anyway, it's all academic. Dual Link DVI is all that matters as far as graphics card ports are concerned.

The only question was re two Monitors, ie. whether cards with a DVI-I x 2 or DVI-I plus DVI-D configuration would have any problem driving two of these monitors, and if they do whether there's any difference.

Right, that's the OP's question (and the answer is no). However I also posted in response to some related/secondary issues raised by ViRGE and mrpiggy. Sorry if it all got a bit muddled
 

MavAnan

Junior Member
Jul 7, 2003
24
0
0
Fair play, TBH I was mixing up (in my mind) my response to you with my earlier response to mrpiggy, who was under the impression that DVI-I wouldn't work
All good but in fairness to mrpiggy, I think he may have been meaning that he thought DVI-I (x2) wouldn't work to drive 2 Monitors. I don't think there's ever been any doubt that a DL DVI-I output is able to drive one Monitor (that's a very common configuration with these Monitors).

Ok I see what you mean. Indeed it could be overkill I suppose, especially if that's what the manufacturer has told them.
yes, I tend to think they're just playing it safe. They want to minimise any reason someone could have for wanting a refund. Be interesting to know if there actually are situations where DVI-I x 2 or DVI-I plus DVI-D wouldn't work to drive 2 of these Monitors.

Right, that's the OP's question (and the answer is no).

So what is the difference between displaying via 2 DVI-I outputs and 2 DVI-D outputs? Is there absolutely nothing different at all?
 
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Black Octagon

Golden Member
Dec 10, 2012
1,410
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So what is the difference between displaying via 2 DVI-I outputs and 2 DVI-D outputs? Is there absolutely nothing different at all?

AFAIK in terms of image quality they are identical. The only difference, again AFAIK, is that the DVI-I ports can output an analogue signal in addition to a digital signal
 

CakeMonster

Golden Member
Nov 22, 2012
1,625
803
136
I run a 2560x1600 monitor and a 2560x1440 monitor on my 7970. One on the Dual Link DVI port, ad one with a DP cable (mini->normal). The included DP->DVI adapter also works.
 

Arkaign

Lifer
Oct 27, 2006
20,736
1,379
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Aside from the good info already given here, I'd like to recommend a new, lower-end card for non-gaming 2560 duty rather than an old 8800. Those old 88xx Nvidia cards were beasts for their time, but are unneccarily hot/loud/thristy, and prone to solder failure after long use.